Chymase is

Options

A. Rennin
B. Activator or prorennin
C. Activator of chymotrypsinogen
D. Gastric juice.

Answer

**Step-by-Step Solution:**

1. **Understanding Chymase**: Chymase is a type of enzyme that belongs to the class of serine proteases. These enzymes are known for their ability to cleave peptide bonds in proteins, which plays a crucial role in protein digestion.

2. **Function of Chymase**: The primary function of chymase is to cleave polypeptides. This means that it breaks down proteins into smaller peptides, which is essential for digestion and various physiological processes.

3. **Location of Chymase**: Chymase is predominantly found in mast cells, which are a type of immune cell involved in allergic responses and inflammation. This location is important as it indicates the role of chymase in immune responses.

4. **Identifying the Correct Option**: The question provides multiple options regarding what chymase is. Given that chymase is an activator of trypsinogen (which is a precursor to chymotrypsin), we can conclude that the correct answer is that chymase is an activator of chymotrypsinogen.

5. **Final Answer**: Therefore, the correct answer to the question "Chymase is" is **Option C: activator of chymotrypsinogen**.

---